Document PS-002
March 16, 2009
Product Specifications for Phase Over Phase GOABS(r)
1.
General
a) This specification covers the design, manufacture, and shipment of phase-over-phase,
1-way, 2-way, 3-way, and 4-way, gang-operated disconnecting switches, both air-break
and load-break, for transmission switching applications
b) All switches furnished shall conform to all applicable IEEE, NEMA, and ANSI standards
c) The switch manufacturer shall furnish all parts required to install a complete operating
switch, including switch frames, operating mechanism, and equipment mounting
hardware; insulators, if required, will be specified separately
d) The pole structure, dead-end assemblies, guying and grounding materials, through
bolts and miscellaneous pole line hardware will be provided by Others
e) This equipment will be field assembled and installed by Others
2.
Applicable Standards and Specifications
a) The following standards shall form a part of this specification unless otherwise stated:
ANSI C29.9
ANSI C37.32
ANSI C37.34
ASTM 123
NEMA SG6
Wet-Process Porcelain Insulators
Schedules of Preferred Ratings, Manufacturing Specifications, and
Application Guide for High Voltage Air Switches
Test Code for High-Voltage Air Switches
Zinc Coating (Hot Dip) on Iron and Steel Hardware
Power Switching Equipment
b) All switches furnished shall be in accordance with the latest versions of the appropriate
specifications.
c) The switch shall be a SEECO type “G” or “GL”, or approved equivalent.
3.
Materials and Workmanship
a) The equipment shall be new and of standard commercial, first-grade quality as to
materials, workmanship, and design, in accordance with the best engineering practice,
and shall be such as has been proven to be suitable for the intended purpose.
b) All welding shall be done by welders experienced in the process to be used and in a
manner evidencing good workmanship.
4.
Environmental Conditions
a) Temperature - Equipment supplied shall be adequate for an operating range of -40
degrees C to +55 degrees C
b) Humidity - Equipment supplied shall be operated under humidity of up to 95% at a
temperature of 40 degrees C
c) Environment - Equipment supplied shall provide reliable performance in environments
with high exposure to salt, minerals, chemicals, or windborne particulate
d) Ice - Equipment supplied shall operate adequate with a build-up of 3/4” clear ice
· P.O. Box 668547 · Charlotte, N.C. 28266
· Phone (704)-392-1396 · Fax (704)-392-7033 · E-Mail info@seecoswitch.com
Southern Electrical Equipment Company, Inc.
Page 1
Document PS-002
March 16, 2009
Product Specifications for Phase Over Phase GOABS(r)
5.
Ratings and Type
a) Type - Switches shall be group operated side-break switches with an integral design
(2-way and 3-way switches), mounted horizontal upright on aluminum support
structures, in a phase-over-phase configuration
b) Ratings - Switches shall meet or exceed the following ratings
Rated Voltage
Rated Maximum Voltage
Rated Frequency
Rated Continuous Current
Rated Momentary Current
Rated Withstand Voltage (BIL)
6.
15 kV through 230 kV
15.5 kV through 242 kV
60 Hz
600 Amp through 3,000 Amp
40 kA through 100 kA
110 kV through 1050 kV
Switch Design and Construction
a)
Jaw Contacts
i)
All jaw contacts shall be silver to copper and designed so that wiping
action is provided with a minimum of roughening or wear on the silver
spherical contacts
ii)
The design of the jaw contacts shall be such that the resultant magnetic
forces during short circuit will tend to hold the blade in the closed position
and maintain contact pressure; blade locks or other latching devices are
not permitted
iii)
Switch contacts shall be the high pressure line contact type with a
minimum of 100 lbs pressure on each silver contact
iv)
Contact pressure shall be maintained by separate back-up spring members independent of the main current path. Contact members shall be
independently adjustable for proper contact deflection
v)
Wear of contacts shall not result in diminished contact performance due to
reduction of contact pressure. The number and size of contact fingers
shall be sufficient to ensure adequate transfer of rated current from the
blade to the jaw
vi)
All contacts shall be self-aligning and self-adjusting and designed to
ensure firm positive contact
b)
Switch Blade
i)
Each switch blade shall form one solid piece and shall be so assembled
that no part of the blade can move relative to another
ii)
Ends of switch blades shall be completely closed except for drain holes
iii)
Rotating-blade switches which require blade locks or latching devices are
not permitted
· P.O. Box 668547 · Charlotte, N.C. 28266
· Phone (704)-392-1396 · Fax (704)-392-7033 · E-Mail info@seecoswitch.com
Southern Electrical Equipment Company, Inc.
Page 2
Document PS-002
March 16, 2009
Product Specifications for Phase Over Phase GOABS(r)
c)
Terminal Pads
i)
Terminal pads on each end of the switch shall be located at the same height
above the insulator
ii)
Terminal pads shall have flat, machined surfaces
iii)
Terminal pads shall have NEMA standard 2-hole arrangement for 600
ampere switches and NEMA standard 4-hole arrangement for switches
rated 1200 to 2000 amperes
d)
Switch Assembly
i)
Switches of the same rating and design shall have interchangeable parts
ii)
The switch shall be so designed that when installed, its operation will not be
prevented by accumulated water, sleet, ice, snow, dirt, or other atmospheric
contamination.
iii)
Metal live parts shall be non-rusting and corrosion resistant. All current
carrying parts shall be non-ferrous.
v)
Live parts shall be designed to use at least three of the four mounting holes
in the insulator or insulator adapter.
vi)
Bolts, screws, and pins shall be provided with lock washers, keys, or
equivalent locking facilities
vii)
No part of the switch blade or jaw assembly, except arcing horns, shall
project lengthwise beyond the terminal pads
e)
Switch Mechanism
i)
The mechanism shall be so designed that all three phases are in positive
continuous control throughout the entire operating cycle
ii)
Each rotating insulator stack shall have double roller or double ball bearings
in the base bearing assembly. Bearing housings shall be weatherproof.
Open type bearing assemblies must be rustproof and non-corroding, and
they shall be designed to completely drain water and moisture accumulation.
iii)
All roller or ball bearings shall be greaseless or maintenance free type
iv)
Rotating insulator stacks with 5” bolt circles (115 kV and greater) shall have
leveling provisions at the base of each stack; rotating insulator stacks with
3” bolt circles (69 kV and below) may employ shims for alignment
v)
All operating pipes shall be sufficiently rigid to maintain positive control
under the most adverse conditions, including a heavily iced switch and
operating mechanism.
vi)
It shall be impossible, after proper and final adjustment has been made, for
any part of the mechanism to be displaced sufficiently, at any point in the
travel, to allow improper functioning of the switch when the switch is opened
or closed at any operating speed
vii)
All ferrous parts, except springs, shall be hot-dip galvanized in accordance
with ASTM A153, latest revision
· P.O. Box 668547 · Charlotte, N.C. 28266
· Phone (704)-392-1396 · Fax (704)-392-7033 · E-Mail info@seecoswitch.com
Southern Electrical Equipment Company, Inc.
Page 3
Document PS-002
March 16, 2009
Product Specifications for Phase Over Phase GOABS(r)
7.
f)
Operating Mechanism
i)
The operating mechanism shall be positively toggled when the switch is
closed to ensure correct, complete switch operation and to provide operating
personnel with visual confirmation
ii)
All vertical operating shafts shall be supported on ball or roller thrust bearings. Guides shall be provided on the vertical shaft at regular intervals to
ensure proper operation.
iii)
Switches rated 230 kV and below shall be furnished with a horizontal swing
handle. Geared mechanisms shall be acceptable, if required, to ensure
proper operation.
iv)
Provision shall be made for padlocking the mechanism in the open or closed
position.
v)
A flexible copper braid shunt shall be provided on the operating mechanism
for ground connections by Others
g)
Switch Frames (Support Structures)
i)
The switch frames shall be an all aluminum design with welded or welded and
bolted construction
ii)
The frame material shall be structural grade aluminum, 6061-T6
iii)
The frame tension rating shall be 10,000 lbs working load, and 16,500 lbs
ultimate
iv)
Angled pull-offs at the tap are permitted with de-rated tensions. Consult the
manufacturer for a schedule of angles and tensions
h)
Arcing Horns
i)
Switches will be supplied complete with high-speed, snap-out arcing horns for
the interruption of limited amounts of line charging and transforming magnetizing currents
ii)
Horns to be constructed from beryllium or stainless steel with appropriate
mechanical and electrical attributes to maintain function throughout the life of
the switch without degradation of spring characteristics
iii)
Horn shall be of a tapered design to provide maximum tip speed
iv)
Arcing horn assembly shall include a mechanical stop (snubber) to prevent
return/rebound of the horn and possible re-strike
Insulators
a) Switches will be supplied without insulators unless specified otherwise on customer’s
RFQ or manufacturer’s proposal
b) Insulators will be wet-process porcelain and conform to ANSI C29.8 and C29.9.
Polymer style insulators can also be supplied at customer request; consult the
manufacturer for guidance on appropriate applications
c) Insulators supplied will be standard strength, ANSI 70 sky-tone gray unless specified
otherwise on customer’s RFQ or manufacturer’s proposal
· P.O. Box 668547 · Charlotte, N.C. 28266
· Phone (704)-392-1396 · Fax (704)-392-7033 · E-Mail info@seecoswitch.com
Southern Electrical Equipment Company, Inc.
Page 4
Document PS-002
March 16, 2009
Product Specifications for Phase Over Phase GOABS(r)
8.
Interrupters
a) Switches requiring load interruption capability shall utilize a vacuum interrupter to interrupt
current and to provide a confined arc when switching load, line charging or transformer magnetizing currents
b) The interrupter unit shall be designed to ensure high speed interruption regardless of the
operational speed of the switch
c) When not being operated, the interrupter unit shall be out of the current path so that it is not
subject to fault currents
d) When the interrupter employs a dielectric to enhance the interrupting rating of the enclosed
vacuum bottle, accidental loss or disposal of the dielectric shall not pose a risk to the health
of utility personnel or the environment; SF6 is not acceptable as a dielectric
9.
Pole Structures
a) Switches may be mounted on pole structures of various types, including wood, laminated
wood, concrete, or steel
b) Switch pole structures must be adequate for the intended purpose, and designed for the
specific loads and line tensions of the switching application; tangent type line structures are
generally discouraged. Consult the switch manufacturer for general guidance, if in doubt
c) Wooden poles, class H1 minimum recommended, are appropriate for switches 69 kV and
below
d) Engineered structures of steel, concrete, or laminated wood, designed for the anticipated load
and line tensions, are recommended for switches rated 115 kV and up
e) For engineered structures, the maximum resultant deflection with worse case ice and wind
loads applied is 2% of the structure height above grade
f) Pole structures must be sized for height to insure adequate clearance for grade to phase,
phase to phase, and phase to shield dimensions. These dimensions vary with the voltage of
the equipment. Consult the manufacturer for a schedule of voltages and dimensions.
10.
Nameplates
a) All switches shall be equipped with a non-corrosive nameplate in accordance with ANSI
C37.30, permanently attached with stainless steel screws or rivets
b) Nameplate shall include the appropriate catalog number, electrical ratings, and manufacturer’s
sales order number for proper and complete identification of the switch
11.
Shipping
a) Switches shall be shipped knocked-down to minimize transportation costs and facilitate
handling and storage
b) Switch live parts shall be completely assembled, and then broken down for shipment. For
switches rated 69 kV and below, base bearings and sub-bases will be assembled and bolted
into position on switch frames
c) Operating pipe will be shipped unassembled and banded together
d) All other switch components shall be shipped in a wooden crate
e) All shipping units will carry a detailed packing slip with part number identification, associated
drawing number and call out, and quantity count; packing slip will also provide the
manufacturer’s sales order number and customer purchase order number
f) All switches and accessories shall be shipped FOB factory, freight prepaid and add unless
otherwise noted
· P.O. Box 668547 · Charlotte, N.C. 28266
· Phone (704)-392-1396 · Fax (704)-392-7033 · E-Mail info@seecoswitch.com
Southern Electrical Equipment Company, Inc.
Page 5